Apparatus for operating valves of steam-engines



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UNITED STATES FrgrTEN'I OFFICE.

NORMAN IV. IVHEELER, OF BROOKLYN, NEIV YORK.

APPARATUS FOR OPERATING VALVES OF STEAM-ENGINES.

Specification of Letters Patent No. 22,320, dated December 14, 1858.

To all whom t may concern:

Be it known that I, NORMAN IV. IVHEELER, of Brooklyn, New York, have invented a new and useful Cut-Oft Motion for Steam- Engines; and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the accompanying drawings, making a part of this specification, in which- Figure l is a sectional elevation of an engine with the cut-ott attached. Fig. 2 a plan. Fig. 3 an end view of the same, and Figs. 4, 5, 6, 7, 8 and 9 views of the separate parts of the devices employed.

In Figs. l, 2, 3, 4, 5 and 6, a is the steam cylinder, B the' piston, C the piston-rod, D the main shaft, E the eccentric and strap, F the eccentric rod, Gr the rock-arm, I-I the rock-shaft and I the rock-arm, which carries a supplemental rock-shaft 3, and arm K, to which the main-valve'rod L is attached. n is another rock-arm upon the rock-shaft H, to which the cut-ott-valve rod O is attached by the sliding block m, which block may be set to different heights by means of the lifting-rod t.

P is a lead-lever attached to the supplemental rock-shaft 3, which is vibrated directly by the cross-head or piston rod, or other reciprocating part moving therewith, by means of the stud Q and link Z, which vibration gives the rod L and valve c a motion equal to its lap and desired lead.

The lap and lead, or idle motion, ot' the main valve being thus provided for, the eccentric E is set upon the main shaft with its throw quite or nearly at right angles with the crank O, and gives the absolute throw to the main valve, through and by means ot' Gr, H and I, carrying with it the rock-shaft 3 and arm K. But the siding cut-o-valve U derives its motion solely from the eccentric E, through F, G, H, N, M, and I.

Now when the engine moves from the position shown (at dead point) the rock-arms G, I and N move from their first position and give motion to the valves, but the riding valve has a greater motion during the early position of the stroke than has the main valve by the negative eiiect of the vibration of the supplementary rock shaft. Hence the throw of the main valve being equal to the throw of I, minus the throw of K, and the throw of the cut-oit valve being equal to the throw of M, it is obvious that the steam will be cut off when the throw of M exceeds the throw of I minus the throw K, by the breadth of the steam ports through the main valve V-and the vibration or throw ot M may be made greater or less by moving it up or down upon n by hand or by means of a governor attached to it.

In Figs. 7 and 8 is seen a device consisting of a link m which is attached at one end to the arm 71, while the other is attached to rock-arnrK, and the main valve-rod O attached to the link in line with its attachment to K. This link m gives motion to the ciit-ol't-v'alve rod R, which, is more or less great, according to the position ot its block T in m.

Fig. 9 shows an arrangement whereby the cubed-valve rod 6 may have the motion of the arm 3, when hooked on to the pin 8, of the rod 7, or the motion of the supplementary rock-arm et, when hooked on to the pin 9, of the main valve rod 5.

It is plain that the motion derived from the movements of the cylinder, as in the engine known as N. IV. I'Vheelers oscillating engine, is. so far as this cut-off motion is concerned, equivalent to the motion derived from the eccentric herein described.

I claim- Actuating the cut-ofil valves of steam engines by means of an eccentric, or its equivalent, when the motion of the main valve is derived from the same eccentric, or its equivalent, but modied'by a movement derived directly from a reciprocating part, substantially as described.

NORMAN IV. IVHEELER.

IVitnesseS c IVM. BAKER, M. R. QUACKENBUSH. 

